[llvm-branch-commits] [llvm-branch] r100481 - in /llvm/branches/Apple/Morbo: ./ lib/Transforms/IPO/FunctionAttrs.cpp lib/Transforms/Scalar/SCCP.cpp

Bill Wendling isanbard at gmail.com
Mon Apr 5 15:25:20 PDT 2010


Author: void
Date: Mon Apr  5 17:25:20 2010
New Revision: 100481

URL: http://llvm.org/viewvc/llvm-project?rev=100481&view=rev
Log:
$ svn merge -c 100478 https://llvm.org/svn/llvm-project/llvm/trunk
--- Merging r100478 into '.':
U    lib/Transforms/Scalar/SCCP.cpp


Modified:
    llvm/branches/Apple/Morbo/   (props changed)
    llvm/branches/Apple/Morbo/lib/Transforms/IPO/FunctionAttrs.cpp   (props changed)
    llvm/branches/Apple/Morbo/lib/Transforms/Scalar/SCCP.cpp

Propchange: llvm/branches/Apple/Morbo/
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Mon Apr  5 17:25:20 2010
@@ -1,2 +1,2 @@
 /llvm/branches/Apple/Hermes:96832,96835,96858,96870,96876,96879
-/llvm/trunk:98602,98604,98612,98615-98616,98675,98686,98743-98744,98768,98773,98778,98780,98810,98835,98839,98845,98855,98862,98881,98920,98977,99032-99033,99043,99196,99223,99263,99282-99284,99306,99319-99321,99324,99336,99378,99418,99423,99429,99455,99463,99465,99469,99484,99490,99492-99494,99507,99524,99537,99539-99540,99544,99570,99575,99598,99620,99629-99630,99636,99671,99692,99695,99697,99699,99722,99816,99836,99845-99846,99848,99850,99855,99879,99881-99883,99895,99899,99910,99916,99919,99952-99954,99957,99959,99974-99975,99982,99984-99986,99988,99992-99993,99995,99997-99999,100016,100035,100037-100038,100042,100044,100072,100074,100081-100090,100092,100094-100095,100116,100134,100184,100209,100214-100218,100220-100221,100223-100225,100257,100261,100332,100353,100384
+/llvm/trunk:98602,98604,98612,98615-98616,98675,98686,98743-98744,98768,98773,98778,98780,98810,98835,98839,98845,98855,98862,98881,98920,98977,99032-99033,99043,99196,99223,99263,99282-99284,99306,99319-99321,99324,99336,99378,99418,99423,99429,99455,99463,99465,99469,99484,99490,99492-99494,99507,99524,99537,99539-99540,99544,99570,99575,99598,99620,99629-99630,99636,99671,99692,99695,99697,99699,99722,99816,99836,99845-99846,99848,99850,99855,99879,99881-99883,99895,99899,99910,99916,99919,99952-99954,99957,99959,99974-99975,99982,99984-99986,99988,99992-99993,99995,99997-99999,100016,100035,100037-100038,100042,100044,100072,100074,100081-100090,100092,100094-100095,100116,100134,100184,100209,100214-100218,100220-100221,100223-100225,100257,100261,100332,100353,100384,100478

Propchange: llvm/branches/Apple/Morbo/lib/Transforms/IPO/FunctionAttrs.cpp
------------------------------------------------------------------------------
--- svn:mergeinfo (original)
+++ svn:mergeinfo Mon Apr  5 17:25:20 2010
@@ -1 +1 @@
-/llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp:99196,99492,99507,99524,99539-99540,99636,99699,99816,99836,99845-99846,99848,99850,99855,99879,99881-99883,99895,99899,99910,99916,99919,99952-99954,99957,99959,99974-99975,99982,99984-99986,99988,99992-99993,99995,99997-99999,100016,100035,100038,100042,100044,100072,100074,100081-100090,100092,100094-100095,100116,100132-100134,100137,100170,100184,100208-100209,100214-100218,100220-100221,100223-100225,100257,100261,100384
+/llvm/trunk/lib/Transforms/IPO/FunctionAttrs.cpp:99196,99492,99507,99524,99539-99540,99636,99699,99816,99836,99845-99846,99848,99850,99855,99879,99881-99883,99895,99899,99910,99916,99919,99952-99954,99957,99959,99974-99975,99982,99984-99986,99988,99992-99993,99995,99997-99999,100016,100035,100038,100042,100044,100072,100074,100081-100090,100092,100094-100095,100116,100132-100134,100137,100170,100184,100208-100209,100214-100218,100220-100221,100223-100225,100257,100261,100384,100478

Modified: llvm/branches/Apple/Morbo/lib/Transforms/Scalar/SCCP.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/branches/Apple/Morbo/lib/Transforms/Scalar/SCCP.cpp?rev=100481&r1=100480&r2=100481&view=diff
==============================================================================
--- llvm/branches/Apple/Morbo/lib/Transforms/Scalar/SCCP.cpp (original)
+++ llvm/branches/Apple/Morbo/lib/Transforms/Scalar/SCCP.cpp Mon Apr  5 17:25:20 2010
@@ -1521,45 +1521,48 @@
       }
     }
   
+    // Check to see if we have a branch or switch on an undefined value.  If so
+    // we force the branch to go one way or the other to make the successor
+    // values live.  It doesn't really matter which way we force it.
     TerminatorInst *TI = BB->getTerminator();
     if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
       if (!BI->isConditional()) continue;
       if (!getValueState(BI->getCondition()).isUndefined())
         continue;
-    } else if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
+    
+      // If the input to SCCP is actually branch on undef, fix the undef to
+      // false.
+      if (isa<UndefValue>(BI->getCondition())) {
+        BI->setCondition(ConstantInt::getFalse(BI->getContext()));
+        markEdgeExecutable(BB, TI->getSuccessor(1));
+        return true;
+      }
+      
+      // Otherwise, it is a branch on a symbolic value which is currently
+      // considered to be undef.  Handle this by forcing the input value to the
+      // branch to false.
+      markForcedConstant(BI->getCondition(),
+                         ConstantInt::getFalse(TI->getContext()));
+      return true;
+    }
+    
+    if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) {
       if (SI->getNumSuccessors() < 2)   // no cases
         continue;
       if (!getValueState(SI->getCondition()).isUndefined())
         continue;
-    } else {
-      continue;
-    }
-    
-    // If the edge to the second successor isn't thought to be feasible yet,
-    // mark it so now.  We pick the second one so that this goes to some
-    // enumerated value in a switch instead of going to the default destination.
-    if (KnownFeasibleEdges.count(Edge(BB, TI->getSuccessor(1))))
-      continue;
-    
-    // Otherwise, it isn't already thought to be feasible.  Mark it as such now
-    // and return.  This will make other blocks reachable, which will allow new
-    // values to be discovered and existing ones to be moved in the lattice.
-    markEdgeExecutable(BB, TI->getSuccessor(1));
-    
-    // This must be a conditional branch of switch on undef.  At this point,
-    // force the old terminator to branch to the first successor.  This is
-    // required because we are now influencing the dataflow of the function with
-    // the assumption that this edge is taken.  If we leave the branch condition
-    // as undef, then further analysis could think the undef went another way
-    // leading to an inconsistent set of conclusions.
-    if (BranchInst *BI = dyn_cast<BranchInst>(TI)) {
-      BI->setCondition(ConstantInt::getFalse(BI->getContext()));
-    } else {
-      SwitchInst *SI = cast<SwitchInst>(TI);
-      SI->setCondition(SI->getCaseValue(1));
+      
+      // If the input to SCCP is actually switch on undef, fix the undef to
+      // the first constant.
+      if (isa<UndefValue>(SI->getCondition())) {
+        SI->setCondition(SI->getCaseValue(1));
+        markEdgeExecutable(BB, TI->getSuccessor(1));
+        return true;
+      }
+      
+      markForcedConstant(SI->getCondition(), SI->getCaseValue(1));
+      return true;
     }
-    
-    return true;
   }
 
   return false;





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